Mfcttrf

Increasingly often, if you Google for a recipe your search results will be full of long, image-rich blog posts that, somewhere in there, have the actual recipe you were looking for. Many of these have a "printer-friendly version" link to make that easier; I can get the stuff I need in my kitchen on paper easily, but the author doesn't have to cut back on the part that is interesting when cooking is not imminent. Here's an example of the basic idea -- if you click on the "print" link it starts your browser print dialogue with a subset of the page's content. But that site made a separate page for the print version, and I want to post the recipe once not twice.

As somebody who sometimes posts about cooking, including recipes, on my blog, I'd like to be able to offer that printer-friendly version, too -- but I don't want to have to create the content twice. Is there some script or HTML magic that can help me? I write my blog posts in markdown and can include HTML tags. How do I modify my source to mark a portion of the post as content for a "print" link (and generate the link)?

CSS supports media queries since Level 2, Revision 1. That's from way back in 2011, so any modern web browser should support it.

If you're able to specify custom CSS, and apply custom CSS classes to your content, then you can define a CSS class such that the pictures and other ancilliary content is shown on screen, but only the actual recipe is printed on paper.

This way, you don't need to have a separate "printer friendly" page, because you're using CSS to define what "printer friendly" means for your particular content. Of course, it assumes that you have control over the CSS in the first place! The person visiting your web site just prints via their browser's normal "print" function.

Specifically, as discussed on MDN, you can either target print media, or a specific characteristic of a media (a feature). For the former, you'd add something like

@media print 
 img.food-photo display: none; 
 body color: black; 

to hide food-photo class imgs and set the text color to black when the rendering media is identified as print.

For the latter, you can target non-color-capable media (whether screen, print, or otherwise) by writing something like

@media not color /* untested, but looks like it should work */ 
 body color: black; 

to set the text color to black where color is not supported.

These can be combined to form even more complex rules, and of course the normal CSS inheritance rules apply as well, so you can override only those attributes that need to be different between, say, print and non-print.

You might also be interested in CSS feature queries, which look to be similar but geared toward even more specific feature support; for example, one example shows how to apply specific CSS depending on whether display: flex is supported. This looks more useful for when you want to know that the user agent (browser) supports a feature, than for targetting specific media types or capabilities.

I came across a Stack Overflow question at What does @media screen and (max-width: 1024px) mean in CSS? which has some more complex examples that you may find enlightening.

I think that the biggest downside to using CSS for this is that it leaves the visitor with no easy way to print the whole page including the "narrative/journey" if that's what they want to do. There are tricks that one can use, but those by their very nature are rather technical.

You could keep the recipe in its own source file. recipeXYZ.html for example. You then dynamically add that source to both your blog post as well as your simplified print page. My jQuery is a bit rusty but something from this SO question should work well.

$("#recipeDiv").load("recipeXYZ.html");

Now you can print from your original page, with its images, or from your print page, which is more printer friendly. You can also modify your recipe from one central location and have it update both pages as they both always receive their content from the same source.

The print page can even be generated dynamically.

<span id="printPreview">print preview</span>

$("#printPreview").click(function()
 var w = window.open(); // you can change the dimenstions of the window here.
 w.document.open().write("recipeXYZ.hml");
 // you probably want to create the actual print button here.
);

You use @media rules in your CSS style sheets to define which html tags you want to print and which are only visible on screen. E.g.

@media print 
 .stuff-you-don't-want-to-print 
 display: none;
 

To print the current browser window, you print it with JavaScript, e.g.

<a href="javascript:window.print()">Print</a>

The page you link to actually provides a separate web page to print. You can see that the URL of the page you print is different than the URL of the blog post. And if you look at the source code the pages are different. So in fact your "example" is an example of what you don't want, when you say that "[you] don't want to have to create the content twice". That page has created the content twice.

If you don't want to create the content twice, use media queries.